When planting forests many plants are set in positions in which they have no possibility to survive. It frequently occurs that the depth of the soil is too small what results in that the plant fades away. Furthermore the distance between planted plants can vary disadvantageously so that the available ground surface is not fully used. A planting operation which is unsuitable in various aspects can also result in that the quality of the wood of the grown-up trees will not be as good as it could else have been.
The cost of reforesting is very high. Manual planting saplings of coniferous trees costs for example about 4 crowns per plant including the cost of purchasing the sapling. The cost of manual planting broad-leaf trees is generally still higher and particularly high is the cost of planting high-grade broad-leaf trees. In many countries there is no time to make plantings in the rate which would be desirable from an ecological and economic aspect since there are no resources for setting aside sufficiently many persons during the planting season. Here in particular USA and Canada can be mentioned. However, the largest problems exist in the developing countries, in which among other things tropical rain forests are sawn and no planned planting of new trees exist. Also in Sweden problems exist of having time for attendance of forests, which is costly owing to the high cost of hired persons.
Thus there is a need for automatic or mechanized planting procedures which should naturally be designed for a rapid and optimized planting, which removes the disadvantages mentioned above and which can result in a planting of plants at optimal positions in the intended ground area.
The commercially available planting machine "Silva Nova" from Storebro Bruk AB is, with a crew of two men, capable of planting up to 1500 plants per hour for good soil conditions. The cost per planted plant comprises approximately the same amount as in manual planting. The machine is in principle a forest vehicle, which has been provided with scarifying wheels having horizontal shafts, which each one is located straight ahead of the tractor wheels in the rear boggy and which turns up a piece of turf under the rear boggy wheels. Behind the same wheels the very planting assemblies are located, one behind each row of rear wheels, which set plants on exactly these positions which have previously been prepared as to the condition of the topsoil.